from django.core.exceptions import PermissionDenied
from django.dispatch import receiver
from django.shortcuts import redirect
from django.urls import resolve, reverse
from django.utils.translation import gettext_lazy as _

from eventyay.control.signals import nav_event_settings
from eventyay.presale.signals import process_request


@receiver(process_request, dispatch_uid='returnurl_process_request')
def returnurl_process_request(sender, request, **kwargs):
    try:
        r = resolve(request.path_info)
    except:
        return

    urlname = r.url_name
    urlkwargs = r.kwargs

    if urlname.startswith('event.order'):
        key = 'order_{}_{}_{}_return_url'.format(
            urlkwargs.get('organizer', '-'), urlkwargs['event'], urlkwargs['order']
        )
        if urlname == 'event.order' and key in request.session:
            r = redirect(request.session.get(key))
            del request.session[key]
            return r
        elif urlname != 'event.order' and 'return_url' in request.GET:
            u = request.GET.get('return_url')
            if not sender.settings.returnurl_prefix:
                raise PermissionDenied('No return URL prefix set.')
            elif not u.startswith(sender.settings.returnurl_prefix):
                raise PermissionDenied('Invalid return URL.')
            request.session[key] = u


@receiver(nav_event_settings, dispatch_uid='returnurl_nav')
def navbar_info(sender, request, **kwargs):
    url = resolve(request.path_info)
    if not request.user.has_event_permission(
        request.organizer, request.event, 'can_change_event_settings', request=request
    ):
        return []
    return [
        {
            'label': _('Redirection'),
            'url': reverse(
                'plugins:returnurl:settings',
                kwargs={
                    'event': request.event.slug,
                    'organizer': request.organizer.slug,
                },
            ),
            'active': url.namespace == 'plugins:returnurl',
        }
    ]
